1. Field of Invention
The invention relates to a pet drinking fountain and, in particular, to an auto water replenishing mechanism of the pet drinking fountain.
2. Related Art
In addition to feeding food, one also needs to supply water for his pet. Traditionally, pet drinking water supply is usually a simple container filled with water. The container can be either closed or open. The size and shape of the container also vary from pet to pet. Such containers simply hold water. On the market, there starts to have containers with cycling water. They mainly utilize a pump to yank up pressure, thereby facilitating dynamical circulation of water. Many pet owners think that such water is good for their pets. However, regardless of what type of container, the pet owner has to take notice when water level is low and resupply the water. Otherwise, the pet will be short of drinking water. Those with pump circulation will further face the problem that the pump motor may fail because of the water shortage.
FIG. 12 shows a pet drinking fountain that can automatically replenish water. Its structure mainly has a water injection element 91 on the container 90 thereof. During water supply, water is injected into the container 90 by a water inlet 910. The water injection element is pivotally provided with a horizontal swing arm 92, whose end is connected with a float 93. The swing arm 92 urges against a sealing plug 94 in the water injection element. The float 93 swings with respect to the pivotal point of the swing arm 92 on the water injection element. When the water level rises, the float rises and drives the swing arm to push the sealing plug 94 to block water inlet 910. When the float drops, the sealing plug 94 retreats from the water inlet 910.
However, the above-mentioned pet drinking fountain with automatic water replenishment has the following problems:
1. The swing arm 92 must have a certain length, so that the swing arm 92 can push the sealing plug 94 to block the water inlet 910 as the float 93 rises with the water level according to the lever principle. Thus, the size of container must be larger than the extended length of the swing arm 92 and the float 93. It is then difficult to reduce the size. Therefore, it is usually used in larger pet drinking fountains. Small pet drinking fountains do not enjoy the function of automatic water replenishment.
2. Since water sources in different regions have different pressures, floats 93 of the same size and swing arm 92 of the same length may have different pushing forces on the sealing plug 94 during the process of replenishing water in the container 90. In a region with larger water pressure, the water inlet may not be completely blocked, resulting in failure of automatic water replenishment.
Therefore, it is the goal of the invention to solve the above-mentioned problems in conventional pet drinking fountains.